From 287123842732ff588248714ec682bcdfda0834d0 Mon Sep 17 00:00:00 2001
From: icex2 <djh.icex2@gmail.com>
Date: Sun, 17 Jan 2021 00:51:22 +0100
Subject: [PATCH] util/rand: Extend, add functions to init with seed, rand u8,
 u16, array

---
 src/main/util/rand.c | 35 ++++++++++++++++++++++++++++++++++-
 src/main/util/rand.h | 16 ++++++++++++++++
 2 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/src/main/util/rand.c b/src/main/util/rand.c
index cbd365d..779fbf0 100644
--- a/src/main/util/rand.c
+++ b/src/main/util/rand.c
@@ -1,7 +1,8 @@
 #include <time.h>
 #include <stdlib.h>
 
-#include "rand.h"
+#include "util/log.h"
+#include "util/rand.h"
 
 static int _util_rand_init = 0;
 
@@ -13,6 +14,22 @@ static void _util_rand_initialize()
     }
 }
 
+void util_rand_init(uint32_t seed)
+{
+    _util_rand_init = 1;
+    srand(seed);
+}
+
+uint8_t util_rand_gen_8()
+{
+    return (uint8_t) util_rand_gen_32();
+}
+
+uint16_t util_rand_gen_16()
+{
+    return (uint16_t) util_rand_gen_32();
+}
+
 uint32_t util_rand_gen_32()
 {
     _util_rand_initialize();
@@ -20,6 +37,11 @@ uint32_t util_rand_gen_32()
     return (uint32_t) rand();
 }
 
+uint32_t util_rand_gen_range_32(uint32_t max)
+{
+    return util_rand_gen_32() % max;
+}
+
 uint64_t util_rand_gen_64()
 {
     uint64_t value;
@@ -31,4 +53,15 @@ uint64_t util_rand_gen_64()
     value |= ((uint64_t) rand());
 
     return value;
+}
+
+void util_rand_gen_bytes(uint8_t* buffer, size_t len)
+{
+    log_assert(buffer);
+
+    _util_rand_initialize();
+
+    for (size_t i = 0; i < len; i++) {
+        buffer[i] = (uint8_t) rand();
+    }
 }
\ No newline at end of file
diff --git a/src/main/util/rand.h b/src/main/util/rand.h
index cc79f0b..2dc74b6 100644
--- a/src/main/util/rand.h
+++ b/src/main/util/rand.h
@@ -3,8 +3,24 @@
 
 #include <stdint.h>
 
+/**
+ * General note for this module: The implementations provided are supposed to
+ * be used for non-security related randomness, e.g. generate some random data
+ * for testing something.
+ */
+
+void util_rand_init(uint32_t seed);
+
+uint8_t util_rand_gen_8();
+
+uint16_t util_rand_gen_16();
+
 uint32_t util_rand_gen_32();
 
+uint32_t util_rand_gen_range_32(uint32_t max);
+
 uint64_t util_rand_gen_64();
 
+void util_rand_gen_bytes(uint8_t* buffer, size_t len);
+
 #endif